CVE-2022-49828 is a vulnerability identified in the Linux kernel related to the handling of HugeTLBFS (Huge Translation Lookaside Buffer File System) pages in the page cache. The issue arises when a 'poisoned' HugeTLB page—indicating a memory error—is detected. Prior to the fix, the kernel would remove such a poisoned page from the page cache. This removal causes subsequent attempts to map or read that hugepage to allocate a new hugepage instead of signaling the memory corruption. This behavior effectively masks the memory corruption, potentially leading to undefined behavior or data integrity issues. The vulnerability is analogous to a previously addressed issue in the shmem subsystem, where similar handling of poisoned pages was corrected. The patch for CVE-2022-49828 changes the behavior to retain the poisoned HugeTLB page in the page cache. If a user-space process attempts to use this poisoned page via a system call, the call will fail with an EIO (Input/Output error), and attempts to map the page will cause the thread to receive a SIGBUS signal with the BUS_MCEERR_AR code, indicating a machine check exception due to a memory error. This approach ensures that memory corruption is properly signaled to user-space applications, preventing silent data corruption or unexpected behavior. The vulnerability affects Linux kernel versions identified by the commit hash 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 and was published on May 1, 2025. There are no known exploits in the wild at this time, and no CVSS score has been assigned.

For European organizations, the impact of CVE-2022-49828 primarily concerns systems relying on Linux kernels that utilize HugeTLBFS for memory management, especially in high-performance computing, virtualization, and database environments where large memory pages are common. The vulnerability could lead to silent memory corruption if unpatched, potentially causing data integrity issues, application crashes, or system instability. This is particularly critical for sectors handling sensitive or critical data, such as finance, healthcare, telecommunications, and government institutions. Although no active exploits are known, the risk lies in undetected memory errors that could compromise system reliability and data correctness. The fix improves error signaling, allowing affected applications and system administrators to detect and respond to memory errors promptly, reducing the risk of data loss or corruption. Given the widespread use of Linux in European enterprise and infrastructure environments, unpatched systems could face operational risks, especially in environments where HugeTLBFS is heavily utilized.

To mitigate this vulnerability, European organizations should: 1) Identify and inventory Linux systems using kernel versions affected by CVE-2022-49828, focusing on those employing HugeTLBFS. 2) Apply the official Linux kernel patches or upgrade to a kernel version that includes the fix for this vulnerability as soon as possible. 3) Implement monitoring for SIGBUS signals and EIO errors in applications that use huge pages to detect potential memory errors early. 4) Conduct thorough testing of applications and services that rely on HugeTLBFS to ensure they handle the new error signaling correctly and fail gracefully. 5) Review system logs and kernel messages for indications of memory errors or page poisoning events. 6) Consider deploying hardware memory error detection and correction mechanisms (e.g., ECC RAM) to reduce the likelihood of memory corruption. 7) Educate system administrators and developers about the implications of poisoned huge pages and the importance of handling related errors properly. These steps go beyond generic patching by emphasizing proactive detection, monitoring, and operational readiness to handle memory errors exposed by this vulnerability.